In FFMpeg 3.5+ the unprefixed CODEC_* constants have been removed, only
the correspondent AV_CODEC_* ones are available.
This fixes a build failure:
.../examples/am7xxx-play.c: In function 'video_output_init':
.../examples/am7xxx-play.c:240:34: error: 'CODEC_FLAG_QSCALE' undeclared (first use in this function); did you mean 'AV_CODEC_FLAG_QSCALE'?
output_codec_ctx->flags |= CODEC_FLAG_QSCALE;
^~~~~~~~~~~~~~~~~
AV_CODEC_FLAG_QSCALE